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Comments 124501 to 124550:

124501. psilax at 01:29 AM on 6 February 2010
        It's microsite influences
        Questions: 1) The belgian media jumped on a result similar to what is posted on http://surfacestations.org/ of summer 2009 (no source reference in Belgian media) in which it seems that a lot of american surface stations have a deviations of more than 1°C and that for some "accurate" surface stations the temperature has been decline the last 100 years. Is this already incorporated in the graphs above? (No post date of the graphs). 2) Why do your graphs only go back to 1980 while other stations have data going back more than 100 years on the graphs of surfacestations.org?
124502. Riccardo at 01:28 AM on 6 February 2010
        On the reliability of the U.S. Surface Temperature Record
        Alexandre, the difference is what they measure. Satellites measure the whole lower troposphere while surface stations just a few (usually two) meters above the surface.
124503. ConcernedCitizen at 00:52 AM on 6 February 2010
        Increasing CO2 has little to no effect
        Some quesitons. 1) Graph one is derrived from the difference between two satelites launched 26 years apart. How are their sensors callibrated so that they would give the same readings on the same day? 2)Graph 2. Why is there no downward radiation for CFCs, HNO3 NO2 etc, as there is for CO2, when the first graph shows that their energy is being 'trapped' in the atmosphere? Additionally. from the picture showing solar light penetrating the atmosphere but terrestrial IR being trapped, what happens to the solar IR? The sun produces aproximately 400000 times as much IR at the frequency absorbed by CO2 as the earth. The atmosphere must therefore absorbs and re-radiate half of this back into space. Also given the far larger solar IR radiation the CO2 will be saturated. Additional IR from the earth is a tiny amount in comparison. Answers appreciated.
124504. Alexandre at 23:14 PM on 5 February 2010
        On the reliability of the U.S. Surface Temperature Record
        A bit OT, yes, but still on temperature records: Sattelite time series, like the UHA, show a much stronger El Nino peak in 1998 (which makes for a favorite source for guys like Watts). Where does the difference come from?
124505. Berényi Péter at 20:43 PM on 5 February 2010
        The role of stratospheric water vapor in global warming
        doug_bostrom at 18:09 PM on 5 February, 2010: "Was there some specific issue with that treatment that bothers you?" Yes, definitely. Just google for "sandpile avalanche dynamics". Highly nonlinear, self-organized sytems (like climate/weather) often show this kind of intermittent behavior. The sloppy phrase used by mainstream climate science to identify phenomena like this is "natural variability". Now. Take a simple sandpile model, generate pile weight time series, apply SNHT and you are left with an ever growing sandpile. The Solomon event is likely just a major "avalanche" among many others, happening all the time on all scales.
124506. Berényi Péter at 20:19 PM on 5 February 2010
        What the IPCC and peer-reviewed science say about Amazonian forests
        Charlie, we have already done with this issue. The "Cruz et al., 2007" reference in the Kehrwald et al. paper is to IPCC AR4, WG II Report, chapter 10. Figure 10.4, letter "s" omitted. http://www.skepticalscience.com/IPCC-2035-prediction-Himalayan-glaciers.html#7875 Basic circular reinforcement technique of new age science at work.
124507. Charlie A at 18:47 PM on 5 February 2010
        What the IPCC and peer-reviewed science say about Amazonian forests
        Peer reviewed literature is not the holy grail many assume. For example, in the 5th assessment report, IPCC can use peer reviewed literature to make essentially the same claims about glacier melting that were made in AR4. A 2008 article published in Geophysical Research Letters states that "“The surface area of glaciers across the TP is projected to decrease from 500,000 km2 measured in 1995 to 100,000 km2 in 2030 [Cruz et al., 2007],” It's right there in peer reviewed literature --- most of the glaciers in the Tibetan Plateau will be gone by 2030! Ref: “Mass loss on Himalayan glacier endangers water resources”, Kehrwald, etal Geophysical Research Letters Vol 35. doi:10.1029/2008GL035556 http://bprc.osu.edu/Icecore/Kehrwald%20et%20al%202008.pdf This article has very many other "interesting" statements. All in a peer reviewed journal. All available for the IPCC to cite in the next assessment report.
124508. Doug Bostrom at 18:09 PM on 5 February 2010
        The role of stratospheric water vapor in global warming
        Berényi Péter at 09:38 AM on 5 February, 2010 "I know what SNHT is supposed to be, even if I've never heard of a Standard Cylinder Compression Test. However, if there is such a thing, it makes sense to test any kind of cylinder the same way which should endure high pressure, not just those in combustion engines, e.g. hydraulic cylinders come to mind." Hah! The second I hit "submit" I knew I'd been insufficiently specific. The point I was trying so foolishly to make is that certain tests are going to be confined in utility to narrow ranges and types of inquiry and that by itself should not and does not mean they are invalid. The specific test I was referring to was one where an IC engine crank and camshaft are rotated such that valves are closed and the cylinder under test is at top of travel. All cylinders in that state should yield reasonably similar pressure readings and should hold that pressure for similar periods of time, all those readings should be within a specification range. This test is an excellent diagnostic for IC engine cylinder wear, would be inapplicable to most other machinery but is nonetheless very valuable as well as uncontroversial. The test you were referring to is used to process not only temperature but also other meteorological readings such as precipitation gathered from multiple sites. It's going to be of no utility in many other fields. It also does not appear to be controversial. I'm not an expert, obviously. Was there some specific issue with that treatment that bothers you?
124509. Doug Bostrom at 17:54 PM on 5 February 2010
        What the IPCC and peer-reviewed science say about Amazonian forests
        thingadonta at 13:51 PM on 5 February, 2010 Your examples of previous instances of natural variability are poor analogies to the situation we are now creating. From various historic examples it appears uncontroversial that we have the ability to exert significant power over various ecological systems, as exhibited by extinctions of various species we've accomplished. The scope of our ability to modify planetary systems also appears rather uncontroversially to have been steadily increasing, as demonstrated by CFC emissions and our subsequent successful initiation of reversal of CFC impacts on the upper atmosphere, or for that matter acidic emissions from industrial sources. These events and the story they tell of our growing capability to harm ourselves beg a couple of questions. Should we continue doing so even after we've developed the skills to perform in a more competent way? Are we in control of ourselves sufficiently to choose the changes we impose? The answers will not come from nature, the responses must come from us.
124510. Pat T at 17:39 PM on 5 February 2010
        It's cooling
        If your kid grows an inch and a half each year between fifth grade and eighth grade and then doesn't grow any more through high school, is he still growing? No. And if someone says "but but but his average height during high school is taller than his average height during middle school!" does that change your mind? It's not still warming. It's still warm. Perhaps it shouldn't be - the known natural forcings over the last decade should perhaps have caused cooling but haven't yet. Is 1998 "cherry picking one year?" No. It's one year of natural variability - but 11, going on 12, years of CO2 emissions. And 1998 is warmer than - or if you use GISS, within 0.01 deg C as warm as, each year since then. If 11 becomes 15 or 20, that's the skeptics' point - - if the climate is as CO2-sensitive as is thought, then no single year of natural variability should offset two decades of cumulative CO2 buildup. 11 hasn't become 15 or 20, so I don't think that "it's still warm though it's neither warming nor cooling" disproves your thesis. So one has to ask, why continue to belabor the point? I understand that "it's still warm even though perhaps it shouldn't be" is complex and you might lose people at the lowest common denominator, but when you oversimplify to the point that you've reduced the thesis to a statement that isn't really accurate, you lose some critical thinkers - as with the "anthropogenic cause of tree ring divergence," this practice probably fuels more skepticism than it quells.
        Response: I understand the use of metaphors but eventually metaphors get so tortured, the usefulness fades. In the case of the 'growing kid' metaphor, an appropriate comparison would be if you had a child that would grow 2 inches in one year, shrink 1 inch the next year, grow 1.5 inches the year after that, shrink .5 inches the next year. His height is shooting up and down but gradually in the long term rising. But really, that's just a weird metaphor!
        
        Don't be beguiled by the year 1998. Be aware that the HadCRUT record which finds 1998 as the hottest year on record doesn't include the whole globe - it excludes regions where the warming trend is greatest. A fully global temperature record finds 2005 as the hottest year on record, 2009 as the 2nd hottest year on record and a statistically significant warming trend throughout this period.
124511. Pat T at 17:20 PM on 5 February 2010
        The hockey stick divergence problem
        1) The spaghetti graph a) has its own issues discussed in climateaudit, b) isn't a hockey stick but rather shows a MWP within half a degree C of late 20th century temps and that lasted a few centuries and didn't result in runaway warming, and c) doesn't include Loehle, which shows a more pronounced MWP. 2) None of the direct evidence for the MWP has been addressed (except for realclimate's thesis that, because after 900 years of breeding grapes for cold-hardiness and advances to growing techniques, they now again have vineyards in England, somehow that means that it must be as warm now as it was when they had vineyards 900 years ago). We're talking about acknowledged history from nearly every corner of the world. If someone were to tell you that based on examination of the Delaware River or the soil underneath it or some other indirect physical proxy, Washington and his men couldn't have crossed it with their horses and gear that night, would you accept this without an explanation as to how it is that the next morning they were on the other side? 3) Right - tree rings are reliable within the temperature range experienced between 1880 and 1960. Above those temperatures they're not reliable - the most obvious explanation is that once you get above the temperatures experienced in 1960, the correlation between tree ring width and temperature falls off. There are other possibilities but there's one clear, obvious explanation that you really have to want to reject in order to reject it. The mental gymnastics engaged in to defend the notion of an anthropogenic explanation for the tree ring divergence is a prime example of what I'm talking about. You fall back on logical contortions to defend aspects of your thesis that could be discarded without jeopardizing your main point. This tendency turns critical thinkers into skeptics. If you just said yep, the MWP was warmer or comparably warm for 200 years but the CO2 we're emitting won't go away and so eventually we're going to have a problem, especially if whatever caused the MWP happens again, I'd be inclined to believe you. There are a lot of skeptics who are skeptics primarily because of this and other needless exaggerations (such as "it's still getting warmer" rather than "it's still warm and it shouldn't be given that natural forcings are have been on the cool side for 3-4 years"). I think the overzealous AGW proponents do their cause more harm than good.
124512. mazibuko at 15:16 PM on 5 February 2010
        What the IPCC and peer-reviewed science say about Amazonian forests
        Thingadonta: "What the WWF fund and other green groups fail to appreciate is that if the forest size reduces/expands quite naturally, why is there so much concern from human activities?" The concern is that human activities alter forest cover far more rapidly than the changes experienced during glacials/inter-glacials. Species adaptation is much easier when a habitat change occurs gradually. A species, particularly an endemic with a narrow range, will struggle to adapt if a large portion (or all) of its habitat is clear-felled within the course of a few months or years.
124513. Tom Dayton at 14:59 PM on 5 February 2010
        What the IPCC and peer-reviewed science say about Amazonian forests
        thingadonta, "a high natural species turnover" contradicts "species adapt to this."
124514. thingadonta at 13:51 PM on 5 February 2010
        What the IPCC and peer-reviewed science say about Amazonian forests
        The Amazon rainforest was severely reduced in size during any of the geologically recent ice ages. This is well-known in the peer reviwed literature. Since these drastic reductions occur naturally, there is no reason to be overly concerned with the forest shrinking/expanding in the first place, (which isn't even mentioned above). The supposed 'lungs of the earth'(a ridiculous term, seeing as northern termperate forests dwarf the size, and effect, on C02 of the Amazon forests) have expanded and receeded markedly during recent glacials/interglacials, meaning all this nonsense about species-area vulneribility with regards to the Amazon is rubbish. There is obviously a high natural species turnover within the Amazon durng glacials/interglacials. Sepcies adapt to this. I the Amazon reduces in size with warming, (which is opposite to what it shoudl do, since it reduces in size with cooling in glacials) its nobig deal. What the WWF fund and other green groups fail to appreciate is that if the forest size reduces/expands quite naturally, why is there so much concern from human activities? It's is a fair question, depsite all the rhetoric.
124515. Riccardo at 09:59 AM on 5 February 2010
        What do the hacked CRU emails tell us?
        To whom it may concern, Penn State inquiry finds no evidence for allegations against Michael Mann. Here the full report of the inquiry panel
124516. Berényi Péter at 09:38 AM on 5 February 2010
        The role of stratospheric water vapor in global warming
        doug_bostrom at 07:35 AM on 5 February, 2010 'Lots of "no" here' I know what SNHT is supposed to be, even if I've never heard of a Standard Cylinder Compression Test. However, if there is such a thing, it makes sense to test any kind of cylinder the same way which should endure high pressure, not just those in combustion engines, e.g. hydraulic cylinders come to mind. If SNHT is a valid statistical procedure, it should make sense to apply it to time series analysis in general, not just climate data. The definition itself is rather formal, never mentioning climate. It is a plain a mathematical procedure. Could you kindly explain why one should not apply it to mortality data? Of course it would be rather easy to get rid of plagues this way, but that's exactly the point.
124517. Marcus at 09:35 AM on 5 February 2010
        The role of stratospheric water vapor in global warming
        RSVP, I was merely saying that a fall in industrial output is *not* the reason for the slower rate of climate change over the last decade, because I've seen no evidence that industrial output *has* fallen. The drop in SWV & TSI are far more likely explanations for the slower rate of warming. Trust me, I am *not* one of those people that goes around saying "we shouldn't do anything about pollution because is just going to fill the gap". Indeed, I really *hate* these people as the cop-outs they are. In truth, China & India are already doing significantly more to reduce their pollution levels-per capita-than what most Western Nations are (with the possible exception of Northern Europe). Hope that clears things up!
124518. Doug Bostrom at 07:35 AM on 5 February 2010
        The role of stratospheric water vapor in global warming
        Ber�nyi P�ter at 07:16 AM on 5 February, 2010 "could you show me a single serious application of the so called "Standard Normal Homogeneity Test" No. Now, let me ask you a question: Can you show me an example of a cylinder compression test used outside of internal combustion engine maintenance? No? Why not? Because it's a technique used for a specific, narrow range of inquiry. Does that mean it has no value? No, again. Lots of "no" here. Learn more about the "Standard Normal Homogeneity Test" here: http://scholar.google.com/scholar?start=60&q=%22Standard+Normal+Homogeneity+Test%22&hl=en&as_sdt=100000000000000
124519. RobM at 07:22 AM on 5 February 2010
        On the reliability of the U.S. Surface Temperature Record
        jpark, Jones never said that the UHI didn't exist, he said it hadn't changed in London over the time period in question. Which makes sense, considering how long the city has been developed.
124520. Berényi Péter at 07:16 AM on 5 February 2010
        The role of stratospheric water vapor in global warming
        guys, could you show me a single serious application of the so called "Standard Normal Homogeneity Test" (SNHT) outside climate science? Anyone?
124521. jpark at 06:39 AM on 5 February 2010
        On the reliability of the U.S. Surface Temperature Record
        HI ys I saw that - if one has to 'correct' for it then presumably Jones was not right in saying it did not exist - which I think is the main point Pielke is making. I will see his son debate with Bob Ward this Friday in London - I hope it is enlightening.
124522. Riccardo at 06:24 AM on 5 February 2010
        Sea level rise is exaggerated
        Arno Arrak, we all know that Al Gore didn't quote any time span for the 20 feet rise. We all also know for sure that the sea level will not stabilze by the end of this century. Comparing Al Gores number with a one century rise is (intentionally?) misleading.
124523. Riccardo at 06:16 AM on 5 February 2010
        On the reliability of the U.S. Surface Temperature Record
        jpark, ironically, the question asked by Pielke Sr. and you has an answer in the very same post. When he quotes Willby paper to assess the UHI effect in London, the very same comparison can be used to check for a difference in the trends. I don't know if Jones at al. used these two stations, but for sure this is the way UHI effect on a trend is checked and corrected for, if any.
124524. Pat T at 04:54 AM on 5 February 2010
        The hockey stick divergence problem
        This just seems like a pattern - when the evidence doesn't support the theory as you've written it, you change the evidence instead of the theory, when it would take only a minor adjustment to the theory to maintain its viability. It's very stubborn, it's unnecessary, and ultimately it detracts from your credibility. Tree ring width is affected by many factors besides temperature. Tree growth is obviously affected by many factors besides temperature - predators, sunlight, water, etc.... You can throw up these other remote possibilities but the obvious explanation is that the linear relationship between tree ring width and temperature breaks down above certain temperatures, which means that the absence of wider tree rings during a given period doesn't mean it wasn't warmer then. Why go to all the effort to string together an alternative thesis just so you won't have to budge on the "hockey stick" when you don't need the hockey stick? Sometimes you're wrong. It's better for your credibility to admit it and move on. It's clever, it's lawyer-like, to come up with "well the divergence must be anthropogenic too" but it's transparent. Don't risk losing credibility over a sub-issue that isn't necessary to make your larger point - - don't lose the forest for the trees!
        Response: I think a few clarifying points are in order as many misconceptions re the hockey stick still prevail:

        1. The hockey stick is not dependent on tree-rings. There are a number of proxies independent of tree-rings that give the same result.
        2. The hockey stick is not the smoking gun proof of human caused global warming. It shows past temperature change, not what's caused it. Sure, it's suggestive and visually persuasive but from a scientific point of view, it does not constitute proof.
        3. The reason tree-rings are considered reliable before 1960 is because there is close correlation between tree-ring proxies and the instrumental record for the periods where the two overlap (Briffa 1998).
        4. Personally, I have no emotional investment in the hockey stick. If it turned out it was erroneous and past climate change was greater than currently thought, this would mean climate is more sensitive than we currently think. This means the climate response to the extra heat trapped by CO2 will be even greater.
        5. Lastly, the peer review science doesn't say the divergence MUST be anthropogenic. It says the "decline in tree growth may have an anthropogenic cause". As the cause is yet to be definitely defined, it's speculation at this point. Similar to the hockey stick, it's not hard proof but it's suggestive. 

        This is not a case of "hockey stick" versus "not a hockey stick". This is a case of considering all the various proxies together and determining what is the most accurate temperature reconstruction.
124525. Svatli at 04:28 AM on 5 February 2010
        What the IPCC and peer-reviewed science say about Amazonian forests
        I'm always surprised when the "argument", "that it's all a lie" comes in to the discussion. But to adress the problem at hand. My view of these matters is that the world is warming up, as the science is making clearer to us by various studies. In the future (even now) there will be climate changes as a result of this warming. Of course there are some uncertanties about how these changes will be in the future, expecially if we are talking about some specific areas (like the Amazonas). But also these changes in climate will have some consequence in the future and science is trying to adress those questions as well as possible, with scientific studys. Of course there will be some mistakes made, but overall I don't think the mistake is the big issue (and of course we'll have to learn from them). With all this noise beeing produced by some "critics" it's going to take more time then it should, but if that's the process we have to go through, well then thats what we'll do. It's amazing how some arguments do evolve and how the small issues are sometimes made to look like as they are the whole picture. The big picture in my mind is that the climate is changing because of human emission of CO2, there will be consequences of these changes, but how severe is up to us, because we are starting to get the pieces together to make the big picture even better.
124526. Pat T at 04:18 AM on 5 February 2010
        The hockey stick divergence problem
        Man-made divergence? That definitely falls into the "oh come on" category. The divergence problem is "unprecedented" and therefore must be anthropogenic? That's quite a reach. The most logical explanation would seem to be that the relationship between tree ring width and temperature changes above a certain temperature level - the level experienced in the 1960s. That means that tree rings are a useful proxy for temperatures up to that level. It also means that tree rings are not useful beyond that level - i.e., it means that when it's warmer than it was in the 1960s, it's not going to show up in tree rings, thus the fact that tree rings don't show higher-than-1960s-temperatures during past periods doesn't mean it wasn't warmer during those periods. And when you take the tree rings out of the equation, voila, the pre-hockey-stick climate history re-emerges. Does the inability to rewrite the climate history preclude man's involvement in the climate changes that have occurred over the last century? No. But the effort to rewrite the climate history adversely affects the credibility of those arguing that man has been deeply involved in those recent climate shifts. So why go through the effort? Tree lines were higher in mountain ranges around the world, including the Sierra Nevadas and Alps. The droughts were so severe in North America that they were a factor in forcing the Anasazi to abandon their elaborate cliffside dwellings. American Indian legend holds that the buffalo migrated far to the north to richer grassland. The Vikings sailed the North Atlantic in wooden boats on ice-free waters (that would during the 14th century become choked with icebergs - i.e., from sea ice breaking off much like today) and maintained a colony on Greenland - and the settlers' diets were for 200 years 80% land-based. They maintained vineyards in England (and the fact that after 900 years of breeding new varieties of grape and improving technology for cold-hardiness British wine production has reemerged is really not a counterpoint). Olive trees in Cologne. Glacial retreat in the Alps is revealing archaeological finds from the MWP - items left behind by traders using mountain passes only now resurfacing. Lake Naivasha in Kenya dried up for 200 years. Further evidence has been found in Mongolia, Japan, the Arctic and Antarctic. And don't forget the countless contemporaneous observations. These have not been explained away as having occurred for reasons other than warmer temperatures, and they cannot be dismissed as "merely anecdotal evidence." These examples all occurred during the 1000 AD - 1200 AD timeframe. That there were a few cold years in between is about as relevant to the "geosynchronous" nature of the MWP as the fact that the United States had its third coldest October on record last year is relevant to geosynchronous warming now. Even if some combination of boreholes and other indirect evidence indicates an MWP slightly cooler than late 20th century temperatures, we still have an MWP plateau that lasted for a few centuries within a few tenths of a degree of the peak modern warmth to date. Rather than try to downplay this or write it out of the climate history altogether, why not simply accept it and try to make the case that the 20th century warming is different because its suspected cause is something that won't reverse itself, which means that it will continue? Why not also point out that since what caused the MWP isn't fully understood, there's every reason to expect that it could reoccur - and that the combined effect of increased CO2 plus whatever naturally caused the MWP would be severe? You might be less able to make a case that we're only a few years away from a "point of no return" but nobody believes that and it's a risky argument anyway - when those few years pass but the point of no return doesn't, it will simply fuel more skepticism. There are a lot of skeptics who would be more open minded about AGW if it weren't for some of the overstatements and misstatements made by the more zealous of AGW supporters, including the efforts to rewrite the climate history. The Hockey Stick has done the AGW proponents more harm than good - when you mess with the established history, you create skeptics of your theories as to the present and future.
124527. Berényi Péter at 04:14 AM on 5 February 2010
        What the IPCC and peer-reviewed science say about Amazonian forests
        Arno Arrak at 02:50 AM on 5 February, 2010: "That the Brazilian forest is sensitive to drought is not a world-changing revelation. [...] idiotic policies that have no effect on climate but [...]" My understanding is that there is not much trend in rainfall over the Amazon basin during the last 60-80 years. If anything, it is increasing slightly. And draught is draught, it just happens every now and then. It is not even true, that biomass decreased there in 2005 tremendously. In most parts of the basin phosynthesis even inreased due to more light from cloudless skies. That is, water availability was not a limiting factor. Deforestration and wildfires is clearly a problem and it is a man-made one. Not through global warming though, but irresponsible land use practices by large corporations whose business is government subsidized biofuel production (soy bean diesel & sugar cane methanol). It is not that Amazon should be left alone. In fact it could support a large population, just some ancient practices are to be picked up again. About 10% of the basin is covered by terra preta, an up to 2 m deep, tremendously fertile black anthropogenic soil, made by a large population between 450 & 1500 AD. Five hundred yers ago most of the people were exterminated by plagues brought in by conquistadors. The rest were hunted by slavers, escaped to forest. Most of the so called primitive tribes there are in fact offsprings of refugees, deprived remnants of a higher civilisation. Considerable part of the basin is not native forest, but an abandoned garden. Terra preta, even after five hundred years with no further care, turned out to be self regenerating. It keeps growing into the barren clay below. The long forgotten technology to create terra preta do indio is already rediscovered, it could also be reimplemented.
124528. Arno Arrak at 04:09 AM on 5 February 2010
        Sea level rise is exaggerated
        Can I point out that your statement about rising sea level is false? B. F. Chao, Y. H. Yu, and Y. S. Li (Science, 320:212-214) have shown that sea level rise for the last eighty years has been linear, with a slope of 2.46 millimeters per year. Theirs is the sea level that has been corrected for the effect of water held in storage by all dams built since the year 1900. Something that has been linear this long is not likely to change anytime soon. Which means that you can be a futurist and predict that sea level will rise a little under ten inches in a century, not twenty feet that Al Gore is still peddling in his movie.
        Response: Arno, thanks for bringing our attention to that paper which actually shows that the situation is worse than I described. The paper is Impact of Artificial Reservoir Water Impoundment on Global Sea Level (Chao 2008). It reconstructs how much water has been impounded in water reservoirs since 1900. The amount of water stored skyrocketed after 1950. If this hadn't occured, sea level would've been even greater. Consequently, they calculate what global sea level should be after accounting for reservoir impoundment water. They then compare their results to actual observed sea level:
        
        
        
        What they find is the increase in the rate of sea level rise is actually greater when you factor in water impoundment. This increases the significance of retreating ice sheets. A sobering result, considering the accelerating ice loss from Antarctica and Greenland.
124529. danielbacon at 03:37 AM on 5 February 2010
        What the IPCC and peer-reviewed science say about Amazonian forests
        You could also add Hutyra et.al. 2005 “Climatic variability and vegetation vulnerability in Amazonia” to your list too. http://eebweb.arizona.edu/faculty/saleska/docs/Hutyra05_Var.Vuln_GRL.pdf
124530. jpark at 03:04 AM on 5 February 2010
        On the reliability of the U.S. Surface Temperature Record
        Leo I think he used Reno because the National Weather Service includes the UHI factor in one of it’s training course using Reno, NV. So says Watts anyway. But this is quite a shock from Pielke blog (link below) where Phil Jones (et Al) is quoted as saying "London however does not contribute to warming trends over the 20th century because the influences of the cities on surface temperatures have not changed over this time." Pielke says: 'However, how would they possibly know that? The assumption that any temperature increase in the last couple of decades in London is not attributable to an increased urban heat island effect, at least in part, needs be documented, for example, by satellite surface temperature measurements for the more recent decades when they are available.' http://pielkeclimatesci.wordpress.com/2010/02/04/the-urban-heat-island-issue-the-released-cru-e-mails-illustrate-an-inconsistency/
124531. Miriam O'Brien (Sou) at 02:36 AM on 5 February 2010
        What the IPCC and peer-reviewed science say about Amazonian forests
        It's my understanding that the IPCC reports themselves are reviewed. Each of the 2007 reports lists a very large number of reviewers. I also thought I saw written on realclimate.org that for at least some of the WG docs the guidelines do not stipulate that all references must only come from peer reviewed journals. I don't have a problem with that provided the IPCC review process works well. The current kerfuffle is likely to result in one of two things: either relevant material will be omitted because, while known, it has not been published in a peer reviewed journal; or material such as potential impacts will be included that are not referenced at all but simply checked by IPCC reviewers for accuracy and relevance, based on their personal knowledge. Neither of these is satisfactory to my mind. I hope that any review of drafting and review processes does not result in important information and likely impacts under specific scenarios being omitted from future reports.
124532. HumanityRules at 01:36 AM on 5 February 2010
        What the IPCC and peer-reviewed science say about Amazonian forests
        And this for a historical view of rainfall in the amazon basin. http://www.scielo.br/pdf/aa/v35n2/v35n2a13.pdf
124533. HumanityRules at 01:05 AM on 5 February 2010
        What the IPCC and peer-reviewed science say about Amazonian forests
        Isn't this a bit of a tautology. Surely by its nature a rainforest ecology is going to be affected by reduction in rain. Just like a saltwater marsh would be affected if its no longer inundated by seawater or a lake system is affected by in flow from rivers. The question is what is the relevance to climate change, what's causing the drying? The 1999 paper specifically links the drought to the 1998 El Nino. There are papers which show that fire has played an important part in amazonian rainforest for over 6000 years. Holocene fires in the northern Amazon basin. Saldarriaga, JG | West, DC Quaternary Research [QUATERN. RES.]. Vol. 26, no. 3, pp. 358-366. 1986. The paper puts forward the hypothesis that there have been "unstable environmental conditions" for >6000years in the Upper Rio Nagro region as evidenced by dated charcoal in the soil. Also http://jisao.washington.edu/data/brazil/ Do you see a trend or fluctuation? Peer-review or WWF is a red herring. The question is relevance.
124534. chris at 00:43 AM on 5 February 2010
        What the IPCC and peer-reviewed science say about Amazonian forests
        chriscanaris, this is a pertinent paper (see below). It addresses the latitude-dependence of expected changes in precipitation in a warming world, and compares this with the observational evidence. The observations and predictins are that the central latitudes experience increased drought in a warming world, whereas the higher latitudes will experience increased precipitation. The region from the equator to ~30 oN is the particularly vulnerable region that is expected to dry fastest, and this has already been observed during the observational period (1925-1999). X. Zhang et al. (2007) Detection of human influence on twentieth-century precipitation trends Nature 448, 461-465 http://www.nature.com/nature/journal/v448/n7152/abs/nature06025.html
124535. CBDunkerson at 00:05 AM on 5 February 2010
        What the IPCC and peer-reviewed science say about Amazonian forests
        chriscanaris, it is fairly obvious that higher temperatures will lead to increased evaporation of surface water and greater quantities of atmospheric water vapor (since the amount of water air can hold increases with temperature). From there it also seems clear that increased atmospheric water vapor will lead to increased precipitation - though not necessarily in direct proportion. However, it needs to be understood that these are localized phenomenon. Increased evaporation drying out scrub-lands is helping the Sahara desert to grow... because that extra evaporation is not offset by equally increased rainfall in northern Africa. The same is true of glacier loss all over the world... higher temperatures are leading to increased melt rate. That extra flowing water does mean increased precipitation, but it is spread out around the world rather than all falling back onto the glacier to replace the mass lost to melting. So your question of whether global warming will lead to a 'wet world' or a 'dry world' isn't really on point... the hydrologic cycle will certainly continue to intensify, but that will result in some areas becoming drier and others wetter... rather than increased evaporation and melt being perfectly offset by increased precipitation in each region.
124536. chris1204 at 22:28 PM on 4 February 2010
        What the IPCC and peer-reviewed science say about Amazonian forests
        Thank you, Alexandre - a fascinating paper. It's an amazingly complex system with many unknowns. Deforestation seems to be a major culprit and perhaps an amplifier of AGW impacts.
124537. Alexandre at 21:46 PM on 4 February 2010
        What the IPCC and peer-reviewed science say about Amazonian forests
        Oh, sorry for the poor citation: Marengo 2006 On the Hydrological Cycle of the Amazon Basin: A historical review and current State-of-the-art
124538. Alexandre at 21:45 PM on 4 February 2010
        What the IPCC and peer-reviewed science say about Amazonian forests
        Since we're talking about the Amazon, here's a Brazilian paper (in English) on water vapour recycling in our rainforest. Climate change is projected to shift rainfall from Amazonia to the La Plata river basin, inducing a permanent El Niño-like behaviour. http://www.rbmet.org.br/port/revista/revista_dl.php?id_artigo=202&id_arquivo=352
124539. chris1204 at 21:33 PM on 4 February 2010
        What the IPCC and peer-reviewed science say about Amazonian forests
        Nevertheless, I really would love to know whether we're likely to be looking at a warm wet world or a warm dry world as it makes a world of difference - pardon the pun. I note the Phillips paper states, ‘Tropical droughts may intensify and become more frequent this century as a result of anthropogenic climate change...’ However, I wonder if this automatically follows if stratospheric water vapour increases. I certainly do have some understanding of probability - a very salient part of my professional field (psychiatry) but I am no climatalogist. However, I hope I can still ask a halfway sensible question. So might increased stratospheric water vapour lead to increased precipitation or does only tropospheric water vapour count? I ought to add that I spent my childhood years 5 degrees north of the equator in West Africa – very warm and very wet! Moreover, Freddy Norton might see dry stressed eucalypts outside assuming he’s living in southeastern Australia (as I do now) – he would encounter a very different environment if he travelled north to the Cape York Peninsula where lush tropical rainforest abounds. As an aside, I note the Phillips paper also says with appropriate caution: ‘We find that relative drought is indeed strongly implicated as the driver of the network-wide shift in forest behavior (Fig. 2) but that the absolute intensity of the 2005 dry period was only weakly related to biomass dynamics... Those forests experiencing the most elevated moisture stress relative to their long-term mean tended to lose the most biomass relative to their pre-2005 trend (Fig. 2). These losses were driven by occasionally large mortality increases and by widespread but small declines in growth. Our method may fail to capture growth impacts well because intervals were longer than the period of potential moisture constraint, thereby masking its effects (drought can kill trees but can only temporarily stop growth).’ Incidentally, Phillips also states: ‘However, our findings do not translate simply into instantaneous flux estimates because carbon fluxes from necromass will lag the actual tree death events.’ This raises the further question of whether ‘necromass’ truly just ‘deadwood’ or is it in fact an intensely complex ecosystem made up of microscopic biomass with its own carbon dynamics and carbon sink properties? Given the exceptional nature of the 2005 drought, I wonder if we don’t run the risk of making long term forecasts based on a single event akin to popular assertions that the severity of the recent northern hemispheric winter ‘disproves’ AGW. It would be more pertinent to ask what is happening to the rainforest five years down the track. Quite a few questions, I know. Any ideas from anyone out there?
124540. Arkadiusz Semczyszak at 21:17 PM on 4 February 2010
        What the IPCC and peer-reviewed science say about Amazonian forests
        Already professor S. Stanley in the "old" textbook: "Earth System History", 1999; for example, African gorillas, and another; reported by high climatic stability of the tropics ... It’s for this, also, in the process of evolution of the coral is not created to adapt to large changes in temperature. This tropical thermostat - it is obvious for climate students... but not for the IPCC ...?
124541. Doug Bostrom at 18:32 PM on 4 February 2010
        What the IPCC and peer-reviewed science say about Amazonian forests
        chriscanaris at 18:24 PM on 4 February, 2010 "I am wary of attributing all environmental problems to AGW" More really a matter of probabilities than definite assignment, and that's where error bars really help. Unfortunately error bars or the equivalent are the very first thing generally stripped away in communications styled for the general public, a shame because they're not at all hard to understand. I think journalists give too little credit to the average reader's ability to keep up. If you're sucked in by the headline and lede, you're probably going to stick around for the whole story as long as it is not egregiously dense.
124542. chris1204 at 18:24 PM on 4 February 2010
        What the IPCC and peer-reviewed science say about Amazonian forests
        Which raises the question of whether the Amazonian drought can be blamed on AGW. The last post on this site dealt with the connection between AGW and stratospheric water vapour. The question is – does increased water vapour lead to increased precipitation? If so, then the Amazonian drought may have its origins in more complex mechanisms. I am wary of attributing all environmental problems to AGW – this detracts from sober assessments of the issues and provides ammunition for those who might have an axe to grind.
124543. RSVP at 18:13 PM on 4 February 2010
        The role of stratospheric water vapor in global warming
        to doug_bostrom "I have neither common sense nor a reputation" ...give yourself more credit. Your reasoning is superb. One of the nice things about having anonymity, as on this site, is that ideas can be shared without fear of damage to reputations. Personally, for a question as large as global survival, its hard to understand how that can even be a priority. At any rate, I believe the truth ultimately "speaks for itself" and will lead humanity in the right direction. But then again, a lot of opportunists will be found along the way.
124544. RSVP at 17:51 PM on 4 February 2010
        The role of stratospheric water vapor in global warming
        Marcus I wrote... "For this reason, it is unlikely for a non skeptic to look for such a correlation, and that any detectible change would have to be coming from natural forcings" then you wrote... "this slower warming rate occurred against a backdrop of a significant drop in Total Solar Irradiance-to levels unseen in over a century" And I cant prove it, but I also KNEW somebody would reply with something like that about China & India. You cant have it both ways. Either it helps to cut back on fossil fuel consumption or it doesnt. The world is never going to get there if everyone is thinking, "well I cant stop this because someone in China is now polluting in my stead", or visa versa. Similarly, it is counterproductive in terms of global morale to be concerned with what the Sun is doing. I cant believe me the skeptic is saying this, but maybe the science behind all this will need to be censored in order to achieve the desired goals.
124545. Doug Bostrom at 17:47 PM on 4 February 2010
        What the IPCC and peer-reviewed science say about Amazonian forests
        The first full explanation of this matter I've seen. Thanks! C&T legislation coming up here in the USA, maybe, and whether that happens will depend a lot on what sort of noise level can be generated by extracting "gotchas" out of IPCC as well as whatever other scat can be flung at climate science. Our legislators here seem to be going through a period of natural or forced variation where the "courage index" is at historical lows, so they'll take any excuse possible to remain sitting on their hands when it comes to serious attacks on carbon. So this is a year-- maybe the first of a few in a row-- where we'll see all the stops pulled out; fossil fuel interests have so much at stake in their battle to avoid us becoming accountable for C02. Readers here may not be aware that even as Dr. Mann is vindicated after Penn State managed to construct a coherent set of inquiry points from skeptic complaints, a new and massive round of FOIA requests are being volleyed by the "Competitive Enterprise Institute".* The very filing of these is eagerly reported by news outlets, regardless of merit, as they feed an air of scandal even where none exists. Some climate scientists are even being sued in connection with their right to free speech.** When it comes to "dragging politics into science", remember where the real political machinations are coming from: CEI, The Heartland Instute, those are the kind of entities projecting politics onto science. No need to imagine scientists engaged in conspiracies, you can read about the real plans in your newspaper, nearly every day. What we're seeing are a number of unwitting researchers blundering onto a stage while pursuing their inquiries, doing what has turned out to be the "wrong" kind of investigation. The stage is filled with actors armed with real swords. It's not a pretty scene, not at all. * http://dotearth.blogs.nytimes.com/2010/02/02/climate-information-wants-to-be-free/#more-13879 http://docs.google.com/fileview?id=0B88iFXWgVKt-Y2VjMTdlNTQtMmJjNy00ZjhkLTkyYTItMzA1Yzc2OTZkYmFi&hl=en ** http://climateprogress.org/2009/11/25/competitive-enterprise-institute-to-sue-realclimate-blogger-over-moderation-policy/
124546. David Horton at 17:44 PM on 4 February 2010
        What the IPCC and peer-reviewed science say about Amazonian forests
        Blind Freddie knows forests, whether in the Amazon, or Australia, are stressed by drought and high temperatures (not to mention fires). From my window I can see Eucalypt forest which visibly changes appearance (I presume as leaves fall, or change orientation, or are reduced in size, or change colour) under extreme conditions. This rubbish about IPCC failures is again (like Himalayan glaciers) a piece of nonsense about the messenger while ignoring the message. "Peer Review" has become one of those terms which is just tossed around, contemptuously by deniers, with approval by those in the real world. I've always thought of the review process not as some magic bullet, removing all error, but as a way of getting your work looked at by someone familiar with the field, who can (a) have some chance, because of familiarity with the field and its literature, spot errors in references, or possible errors in tables, or see some error in logic, and (b) reassure you that you are not living in some alternative universe. Non-peer-reviewed material is the shock jock on the radio, Monckton at the press club, Plimer's book, most blogs (although in a sense the comments on a blog piece are a form of peer review, as long as your readers are not all raving lunatics). These are just statements made, out of someone's thought processes, or whacky experiment, which sees publication without anyone else getting to check it. Non-peer-reviewed papers may occasionally be right, of course, peer reviewed ones may retain errors (no one really knows the details of your subject as well as you do). It's all a bit like the difference between getting a PhD after being vetted by your supervisor and three hot shot examiners, and getting a PhD by filling in a form and sending money to an internet site in Uzbekhistan.
124547. Doug Bostrom at 12:08 PM on 4 February 2010
        The role of stratospheric water vapor in global warming
        Marcus: "First off there has been *no cooling* for the last 10 years, just a slower rate of warming than what we saw between 1980-1999." And it's great that Solomon's paper advances a possible explanation for this. Beyond Solomon, there is no identified mechanism to explain why the Earth should appear to have undergone cooling during the past decade. More, for that matter there is not even a means to explain a slowdown in warming of the size we've seen, not one on which anybody's prepared to stake their reputation. Solomon explains perhaps 25% of the budget problem, leaving a hole that while not a complete mystery is not actually attributable on a quantified basis to any of several possible candidates. Consider for a moment that the first 3 meters of the ocean contains as much heat energy as the entire atmosphere, that the ocean has an average depth of some 3,800 meters, with the vast bulk of that water exchanging heat with the atmosphere as well as directly absorbing much larger amounts from insolation at greater or lesser rates. The upper 90m of ocean alone introduces potentially years of delay for measurable surface temperature changes in response to forcings. Now remember that our ability to measure ocean heat content is patchy while our understanding of the movement of heat into the oceans particularly as water and heat goes deeper via thermohaline circulation is by no means perfect. We can't say on an annual basis or even over a number of years how much energy the ocean will suck up in a way that keeps the ever-so-wispy atmosphere cooler than it would be without the ocean sink. We obsess about surface temperatures while in point of fact a miniscule fraction of the energy imbalance predicted by climate science is actually available for measurement at the surface. Most of the energy is going into the ocean, at greater or less rates over time, where it may be hidden for greater or lesser periods of time. I don't think anybody with common sense and a scientific reputation to protect will make a firm prediction about the ocean heat sponge vis-a-vis the past decade in the absence of more actual data. I have neither common sense nor a reputation, so I'll say that in years to come we'll likely find there was little total change in the radiative budget during the past decade and that instead this heat has been temporarily "lost" in the ocean. More on ocean: http://www.oco.noaa.gov/index.jsp?show_page=page_roc.jsp&nav=universal
124548. Marcus at 11:18 AM on 4 February 2010
        The role of stratospheric water vapor in global warming
        RSVP. First off there has been *no cooling* for the last 10 years, just a slower rate of warming than what we saw between 1980-1999. Secondly, this slower warming rate occurred against a backdrop of a significant drop in Total Solar Irradiance-to levels unseen in over a century. It had little to do with economic activity, given that 2001-2007 marked a large upswing in economic activity in most parts of the world-especially China & India (the GFC is only a very recent event after all). So your theory about warming being potentially due to industrial waste heat doesn't actually bear up to close scrutiny. Even so, turning waste heat from industry into electricity is a good idea because it reduces both thermal pollution (which, IMHO, is a problem we should be tackling) whilst also reducing our dependence on fossil fuels as an immediate source of electricity.
124549. RSVP at 10:50 AM on 4 February 2010
        The role of stratospheric water vapor in global warming
        The warming period happens to coincide with a period of economic boom (the 90s), while the cooling comes after ten years of economic crisis. It is well known that the affluent heat polluters of the planet have had to curb their spending habits in direct relation to the crisis and increased fuel prices. On the other hand, if the effects of CO2, as the theory goes, has such a prolonged hysteresis (in the order of hundreds of years), changes in life style within this ten year span shouldnt make a dent in temperatures. For this reason, it is unlikely for a non skeptic to look for such a correlation, and that any detectible change would have to be coming from natural forcings. (If this recent cooling is indeed due to a slowed down global economy, it would suggest extra warming is due primarily to industrial waste heat.) Without jumping to conclusions, this touches on the issue of climate response, or what has been referred to in other posts as sensitivity. If an Earth Year was conducted (like Earth Day except for a year, and with participants truely not burning any fossil fuels), and if after that year, global cooling was detected, an index for the Earth's response to human industry could be determined, where a faster response would indicate higher sensitivity, and a slower response, lower sensitivity. Ironically, higher sensitivity would be bad, since it would indicate a need for drastically curbing human industry. On the other hand, low sensitivity would also be bad, because it would indicate that we have little or no control of this situation. More ironic still is that I am supposedly a skeptic.
124550. Berényi Péter at 10:05 AM on 4 February 2010
        The role of stratospheric water vapor in global warming
        CO2 does play an important part. In tropical lower stratosphere (~15 km), above low level clouds it has a vehement cooling effect. Temperature there can get as low as 190 K. Air becomes absolutely dehydrated (0.2 ppmv dihydrogen monoxide). Up there CO2 is the main agent, capable to radiate heat out to even cooler (2.7 K) space. The more CO2 is in the atmosphere, the more dryfreezed air is produced this way. If subsequently it gets mixed into upper troposphere by whatever process and drifts over a cloudless area, a wide IR window is opened, an effective heatsink to space. http://asd-www.larc.nasa.gov/~tak/wong/images/NationalGeographic/ceres_aqua_olr3d_20030804_s.png

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